title: Extracorporeal membrane oxygenation versus counterpulsatile, pulsatile, and continuous left ventricular unloading for pediatric mechanical circulatory support.
abstract: OBJECTIVE
  Despite progress with adult ventricular assist devices, limited options exist to support pediatric patients with life-threatening heart disease. Extracorporeal membrane oxygenation remains the clinical standard. To characterize (patho)physiologic responses to different modes of mechanical unloading of the failing pediatric heart, extracorporeal membrane oxygenation was compared to intra-aortic balloon pump, pulsatile-flow ventricular assist device, or continuous-flow ventricular assist device support in a pediatric heart failure model.
  
  
  METHODS
  Experimental.
  
  
  METHODS
  Large animal laboratory operating room.
  
  
  METHODS
  Yorkshire piglets (n = 47; 11.7 ± 2.6 kg).
  
  
  METHODS
  In piglets with coronary ligation-induced cardiac dysfunction, mechanical circulatory support devices were implanted and studied during maximum support.
  
  
  RESULTS
  Left ventricular, right ventricular, coronary, carotid, systemic arterial, and pulmonary arterial hemodynamics were measured with pressure and flow transducers. Myocardial oxygen consumption and total-body oxygen consumption were calculated from arterial, venous, and coronary sinus blood sampling. Blood flow was measured in 17 organs with microspheres. Paired Student t tests compared baseline and heart failure conditions. One-way repeated-measures analysis of variance compared heart failure, device support mode(s), and extracorporeal membrane oxygenation. Statistically significant (p < 0.05) findings included 1) an improved left ventricular blood supply/demand ratio during pulsatile-flow ventricular assist device, continuous-flow ventricular assist device, and extracorporeal membrane oxygenation but not intra-aortic balloon pump support, 2) an improved global myocardial blood supply/demand ratio during pulsatile-flow ventricular assist device and continuous-flow ventricular assist device but not intra-aortic balloon pump or extracorporeal membrane oxygenation support, and 3) diminished pulsatility during extracorporeal membrane oxygenation and continuous-flow ventricular assist device but not intra-aortic balloon pump and pulsatile-flow ventricular assist device support. A profile of systems-based responses was established for each type of support.
  
  
  CONCLUSIONS
  Each type of pediatric ventricular assist device provided hemodynamic support by unloading the heart with a different mechanism that created a unique profile of physiological changes. These data contribute novel, clinically relevant insight into pediatric mechanical circulatory support and establish an important resource for pediatric device development and patient selection.
authors.affiliation: 1Division of Cardiovascular Surgery, University of Pennsylvania, PA. 2MD/PhD Program, University of Louisville School of Medicine, Louisville, KY. 3Cardiovascular Innovation Institute, University of Louisville, Louisville, KY. 4Department of Bioengineering, University of Louisville, Louisville, KY. 5Department of Surgery, University of Louisville, Louisville, KY.
authors.forename: Carlo R
authors.initials: CR
authors.lastname: Bartoli
authors.forename: Steven C
authors.initials: SC
authors.lastname: Koenig
authors.forename: Constantine
authors.initials: C
authors.lastname: Ionan
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Gillars
authors.forename: Mike E
authors.initials: ME
authors.lastname: Mitchell
authors.forename: Erle H
authors.initials: EH
authors.lastname: Austin
authors.forename: Laman A
authors.initials: LA
authors.lastname: Gray
authors.forename: George M
authors.initials: GM
authors.lastname: Pantalos
mesh_terms: D000818:Animals; D001011:Aorta / Q000503:physiopathology; D002339:Carotid Arteries / Q000503:physiopathology; D003331:Coronary Vessels / Q000503:physiopathology; D015199:Extracorporeal Membrane Oxygenation; D006333:Heart Failure / Q000503:physiopathology* / Q000628:therapy*; D006352:Heart Ventricles / Q000503:physiopathology; D006353:Heart-Assist Devices; D006439:Hemodynamics; D007423:Intra-Aortic Balloon Pumping; D010101:Oxygen Consumption; D011673:Pulsatile Flow / Q000502:physiology; D012079:Renal Circulation; D013552:Swine